1. Field of the Invention
The present invention relates to a connecting member for surface mounting circuit for mobile phone and the like.
2. Description of the Related Art
Previously, for connecting a metal connecting member, for a surface mounting circuit with a circuit, pattern of a main circuit board, soldering of a metal terminal of the connecting member and the circuit pattern provides a sufficient connecting strength. However, recent electronic devices are equipped with multiple functions; mobile phone has such functions as digital camera, Internet tool, GPS apparatus, and television. Electronic devices' multi-functionization and miniaturization causes a need to make both the width of a circuit pattern on a printed circuit board and the pitch between those circuit patterns much narrower into a micron order. In such a situation, the conventional mechanical connection by soldering no longer provides a sufficient connecting strength. Therefore, in recent years, an insulating adhesive agent is used for reinforcing the connecting strength.
The above-mentioned functions such as digital camera, television, GPS, inter-net, and the like are mounted on a small board of the sub-board and made into a module. A connecting member for mounting those functional members on a printed circuit board is connected to the printed circuit board by mechanical bonding with soldering and by chemical bonding with adhesive agent.
The substrate of the connecting member is made of electrically insulating thermoplastic resin such as liquid crystal polymer, heat-resistant polyamide, or polyphenylene sulfide, and is formed by injection-molding of those resins. However, a property of good adhesion does not belong to any of the liquid crystal polymer, heat-resistant polyamide, and polyphenylene sulfide.
Further, it is inevitable that portable mobile electronic devices such as a mobile phone, portable computer, or digital camera, drop by accident while handled. If a mobile phone drops, a weight of its own multiple function module mounted on the sub-board directly hits its own printed circuit board, to break the electric connection between the printed board and the module.
Facing such a new problem of accidental dropping of the electronic devices, increase of adhesive strength between their connecting member and electronic circuit board is desired to improve their shock resistance level against dropping.